‘Problems everywhere’: Water so low in massive reservoir that an intake valve is now exposed
Mike Snider, USA TODAY, 11:07am, May 1, 2022
- The emergence of an intake valve on Lake Mead this week drew attention to falling water levels there.
- But water levels at Lake Mead and Lake Powell have been falling amid drought conditions the past two decades.
- Federal and state officials are attempting to find ways to secure the Colorado River water resources which serve more than 40 million people.
When the water level in a dam falls so low that an intake valve becomes exposed, you know the lake is in trouble. But when that happened this week at Lake Mead, it didn’t surprise experts or state and federal officials.
They have known that Lake Mead, the nation’s largest manmade reservoir and home to Hoover Dam, has is hitting historic low water levels, threatening the water supply for as many as 25 million people in the western U.S.
Water levels at Lake Mead, located in Arizona and Nevada, have dropped to elevation 1,055 feet, the lowest since 1937, a year after Hoover Dam became operational and created the reservoir. In comparison, Lake Mead was at elevation 1,080 feet this time a year ago – a year in which federal officials declared a water shortage for southwestern U.S. areas served by Lake Mead.
‘Death by 1,000 cuts’: How the US Forest Service is losing a war over water in the West
But additional attention turned to Lake Mead this week when images emerged on social media and in a CNN story about one of the lake’s intake valves appearing above the falling water line for the first time.
Water from Lake Mead drains into valves located toward the bottom of the lake. These “intake valves” help transport the water to water treatment plants, where it is processed into drinking water.
“That intake valve you saw (at Lake Mead) is just a manifestation of problems everywhere in the (Colorado River) basin,” said Brad Udall, senior water and climate research scientist for the Colorado Water Institute at Colorado State University. That includes “really low levels at Lake Powell,” located on the river to the northeast, he said.
Lake Mead’s decline is not happening in isolation, but is the result of a two-decade drought hitting the western U.S. and causing critical water shortages on the Colorado River.
Water levels at Lake Powell, too, have hit historic lows, falling below a mark set by federal officials to ensure power production and enough water storage to supply Lake Mead and other Colorado River users downstream. Both lakes were full in the year 2000, but now are roughly 30% full, Udall said.
A word being used to describe the “long-term warming and drying of the American West,” is aridification, he said.
“Not every year is warmer, not every year is drier, but that is the overall trend,” Udall said. “We now have much higher evaporation in all its forms and that means less water, less snow gets to the river … This drought is not going away. It’s a serious problem. It’s going to have to be dealt with and it’s going to be really painful.”
Human-caused climate change has contributed to the “megadrought,” the worst intense dry spell to hit the region since at least the year 800, researchers said in a study published in February in the peer-reviewed British journal Nature Climate Change.
West’s drought has no end in sight:‘If we do nothing, it’s going to be really bad’
Steps to protect Lake Powell
The seven states that rely on the Colorado River for water supply – Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming – have agreed to cut back on the amount of water to be released this year from Lake Powell into Lake Mead by 480,000 acre-feet, more than 156 billion gallons. 500,000 acre-feet of water will also be released from Utah’s Flaming Gorge reservoir into Lake Powell.
They hope those steps help “reduce the risks we all face,” the states said in a letter dated April 22 to Tanya Trujillo, the assistant interior secretary for water and science. Two weeks earlier, Trujillo had asked the states to consider the move to avoid “unprecedented operational reliability challenges” for the Glen Canyon Dam on Lake Powell.
If Lake Powell’s level falls too low – below 3,490 feet, it’s currently at about 3,520 – the infrastructure supplying drinking water to the city of Page, Arizona and the LeChee Chapter of the Navajo Nation “could not function,” Trujillo said.
Additionally, if water levels decrease too much, the dam would be unable to generate electricity, which could bring “uncertain risk and instability” to the western U.S. electrical grid, she said. The dam’s powerplant supplies electric power to Wyoming, Utah, Colorado, New Mexico, Arizona, Nevada and Nebraska.
In other moves, Nevada and California and the U.S. Bureau of Reclamation will reduce water use by at least 500,000 acre-feet in 2022 and again in 2023.
Colorado River situation ‘very serious’
Earlier this month, the Colorado River, which helps provide water for more than 40 million people, was rated the nation’s most endangered by conservation group American Rivers in its annual America’s Most Endangered Rivers report.
“Failure is simply not an option, given all that depends on a healthy, flowing Colorado River,” said the organization’s president and CEO Tom Kiernan in announcing the report. “On the Colorado River and nationwide, the climate crisis is a water crisis. Just, equitable solutions for rivers and clean water are both achievable and essential to our health, safety, and future.”
The Southern Nevada Water Authority had prepared for lower water levels on Lake Mead by completing in 2015 a third intake valve capable of getting water, should levels fall below 1,000 feet. And more recently, in 2020, the authority also finished work on a low lake level pumping station, which can get water from the lake should its elevation drop to 875 feet.
The authority is also pushing conservation efforts including offering rebates to homeowners who replace grass with water-smart landscaping. “The situation on the river is very serious,” said Colby Pellegrino, deputy general manager of resources for the Las Vegas Valley Water District and the Southern Nevada Water Authority.
As federal and state officials attempt to find short-term initiatives to manage decreased water resources, they also face the 2026 expiration of the current Colorado River management guidelines.
Scientists say this may be “the new normal and it could be worse than what we’re seeing today,” Pellegrino said. “We have to do more to bring our demands in line with what Mother Nature’s providing us.”